Dual sided image reading apparatus and method to print sides using different options

ABSTRACT

An image reading apparatus to prevent reading quality from deteriorating when two reading units respectively read a first side and a second side of a document with different capabilities, and a method of controlling the same includes an automatic document feeder to feed a document, a first reading unit to read a first side of the document fed by the automatic document feeder, and a second reading unit to read a second side of the document fed by the automatic document feeder. A control unit to control an operation of the image reading apparatus determines at least one of the first reading unit and the second reading unit as a reference reading unit in a both-side reading mode in which both sides of the document are read and controls a transport speed of the document such that the document is transported at a speed to allow the reference reading unit to read the document.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 12/107,925 filed Apr. 23, 2008, which claims priority under 35U.S.C. §119(a) from Korean Patent Application No. 2007-74163, filed onJul. 24, 2007 in the Korean Intellectual Property Office, the disclosureof which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present general inventive concept relates to an image readingapparatus, and, more particularly, to an image reading apparatus to readimage information recorded on a first side and a second side of adocument with different capabilities and a method of controlling thesame.

2. Description of the Related Art

An image reading apparatus reads image information recorded on adocument and is mounted in a machine such as a scanner, a digital copieror a multi-function machine.

A method of reading both sides of a document in an image readingapparatus may be classified into two methods. There is a method ofreading a first side of a transported document via a reading unit,changing a transport direction of the document via a document directionchanging device, reversing the first side and a second side of thedocument via a duplex path, and reading the second side of the document.Such a method is advantageous in that the both sides of the document canbe read using one reading unit, but is disadvantageous in an amount oftime required to read the both sides of the document.

There is also a method of reading both sides of a document by mounting afirst reading unit to read a first side of the document and a secondreading unit to read a second side of the document to be opposed to eachother. Such a method is advantageous in that the both sides of thedocument can be simultaneously read without unnecessarily circulatingthe document and thus a both-side reading operation can be performedwith a high speed.

When both sides of a document are read using an image reading apparatusemploying the latter method, a user may want to read a first side and asecond side of the document with different capabilities as needed. Forexample, when a document having a first side on which a picture or adrawing is recorded and a second side on which only characters arerecorded is read, the user may want to read the first side with a highresolution and read the second side with a low resolution. In addition,the user may want to read the first side of the document in full-colorand to read the second side of the document in monochrome.

However, if the document is read without considering the reading optionswhich are respectively selected by the user with respect to the tworeading units are different from each other, at least one of the tworeading units cannot sufficiently perform a function thereof and thusreading quality deteriorates.

SUMMARY OF THE INVENTION

The present general inventive concept provides an image readingapparatus to prevent reading quality from deteriorating when two readingunits respectively read a first side and a second side of a documentwith different capabilities, and a method of controlling the same.

Additional aspects and utilities of the present general inventiveconcept will be set forth in part in the description which follows and,in part, will be obvious from the description, or may be learned bypractice of the general inventive concept.

The foregoing and/or other aspects and utilities of the generalinventive concept may be achieved by providing an image readingapparatus including an automatic document feeder to feed a document, afirst reading unit to read a first side of the document fed by theautomatic document feeder, a second reading unit to read a second sideof the document fed by the automatic document feeder, and a control unitto determine at least one of the first reading unit and the secondreading unit as a reference reading unit in a both-side reading mode inwhich both sides of the document are read and control a transport speedof the document such that the document is transported at a speed toallow the reference reading unit to read the document.

The control unit may estimate a time necessary for the first readingunit to read image information of the document with a time necessary forthe second reading unit to read image information of the document anddetermine at least one of the first and second reading units, which hasa longer time, as the reference reading unit.

The control unit may estimate a time necessary to store image data readby the first reading unit with a time necessary to store image data readby the second reading unit and determine at least one of the first andsecond reading units, which has a longer time, as the reference readingunit.

The control unit may compare a reading resolution of the first readingunit with a reading resolution of the second reading unit and determineat least one of the first and second reading units, which has a higherreading resolution, as the reference reading unit.

The control unit may control the first reading unit or the secondreading unit such that a time interval in which at least one of thefirst and second reading units, which is not the reference reading unit,reads image information from the document is increased.

The foregoing and/or other aspects and utilities of the generalinventive concept may also be achieved by providing an image readingapparatus including: first and second reading units to respectively reada first side and a second side of a document with differentcapabilities, and an automatic document feeder to feed the document at aspeed to allow at least one of the first and second reading units, whichhas a higher reading resolution, to read the document.

The foregoing and/or other aspects and utilities of the generalinventive concept may also be achieved by providing a method ofcontrolling an image reading apparatus including first and secondreading units to respectively read a first side and a second side of atransported document, the method including: determining at least one ofthe first reading unit and the second reading unit as a referencereading unit in a both-side reading mode in which both sides of thedocument are read, and controlling a transport speed of the documentsuch that the document is transported at a speed to allow the referencereading unit to read the document.

The determining of the reference reading unit may include estimating atime necessary for the first reading unit to read the document with atime necessary for the second reading unit to read the documentaccording to a reading option selected by a user and determining atleast one of the first and second reading units, which has a longertime, as the reference reading unit.

The determining of the reference reading unit may include comparing areading resolution of the first reading unit with a reading resolutionof the second reading unit and determining at least one of the first andsecond reading units, which has a higher reading resolution, as thereference reading unit.

The foregoing and/or other aspects and utilities of the generalinventive concept may also be achieved by providing an image formingapparatus including a first reading unit to read one side of thedocument, a second reading unit to read an other second side of thedocument, an input unit to provide first reading options correspondingto a first reading unit and second reading options corresponding to asecond reading unit from which a user can select, and a control unit toselectively control the first reading unit and the second reading unitbased on the respective first and second reading options selected by theuser.

The respective option selected by the user for each of the first readingunit and the second reading unit are different from each other.

The first and second reading options include a color capability, amonochrome capability and resolution capabilities.

The control may selectively control a transport speed of the document tothe first reading unit and the second reading unit based on therespective first reading options and second reading options selected bythe user.

The foregoing and/or other aspects and utilities of the generalinventive concept may also be achieved by providing an image formingapparatus including providing first reading options corresponding to afirst reading unit and second reading options corresponding to a secondreading unit from which a user can select, and selectively controllingthe first reading unit and the second reading unit based on therespective first and second reading options selected by the user.

The foregoing and/or other aspects and utilities of the generalinventive concept may also be achieved by providing a computer-readablerecording medium having embodied thereon a computer program to execute amethod, wherein the method includes providing first reading optionscorresponding to a first reading unit and second reading optionscorresponding to a second reading unit from which a user can select, andselectively controlling the first reading unit and the second readingunit based on the respective first and second reading options selectedby the user.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects and utilities of the present inventiveconcept will become apparent and more readily appreciated from thefollowing description of the embodiments, taken in conjunction with theaccompanying drawings of which:

FIG. 1 is a view illustrating a configuration of a multi-functionmachine having an image reading apparatus according to an embodiment ofthe present general inventive concept;

FIG. 2 is a view illustrating a configuration of the image readingapparatus according to an embodiment of the present general inventiveconcept;

FIG. 3 is a block diagram illustrating the image reading apparatusaccording to an embodiment of the present general inventive concept; and

FIG. 4 is a flowchart illustrating a method of controlling the imagereading apparatus according to an embodiment of the present generalinventive concept.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Reference will now be made in detail to embodiments of the presentgeneral inventive concept, examples of which are illustrated in theaccompanying drawings, wherein like reference numerals refer to the likeelements throughout. The embodiments are described below in order toexplain the present general inventive concept by referring to thefigures.

FIG. 1 is a view illustrating a configuration of a multi-functionmachine having an image reading apparatus according to an embodiment ofthe present general inventive concept,

FIG. 2 is a view illustrating a configuration of the image readingapparatus according to an embodiment of the present general inventiveconcept, and FIG. 3 is a block diagram illustrating the image readingapparatus according to an embodiment of the present general inventiveconcept.

As illustrated in FIG. 1, the multi-function machine includes an imagereading apparatus 100 to read an image recorded on a document and aprinting apparatus 200 to print an image on a document.

The printing apparatus 200 prints an image according to a signal inputfrom the image reading apparatus 100 or input from an external apparatussuch as a personal computer (PC). The printing apparatus 200 includes adocument feed unit 210 to feed a document S which is a printing medium,a development unit 220 to develop an image on the document, a fixingunit 230 to apply heat and pressure to the document and fix thedeveloped image to the document, and an ejection unit 240 to eject thedocument on which the image is printed.

The document S loaded on a document tray 211 is picked up by a pickuproller 212 and is transported to the development unit 220. Anelectrostatic latent image is formed on the surface of a photosensitivedrum 221, which is charged with a predetermined potential by a chargingroller 222, by an exposure unit 250. The electrostatic latent image isdeveloped to a toner image by a development roller 223 and istransferred onto a document by a transfer roller 224. The toner imagetransferred onto the document is fixed to the document by heat andpressure when passing between a heating roller 231 and a pressurizationroller 232 of the fixing unit 230, and the document passing through thefixing unit 230 is transported and ejected by an ejection roller 241.

As illustrated in FIGS. 2 and 3, the image reading apparatus 100according to embodiments of the present general inventive conceptincludes a reading apparatus main body 101 including a reading frame 110and a cover 120, an automatic document feeder (ADF) 130 to automaticallyfeed a document such that a reading operation can be continuouslyperformed, first and second reading units 140 and 150 to irradiate lightonto a document D and read image information, and a control unit 160 tocontrol an entire operation of the image reading apparatus 100 accordingto an input signal of a user and a predetermined program.

The first reading unit 140 and the second reading unit 150 irradiatelight onto the document D, detect light reflected from the document,convert the amount of light into an electrical signal, and send theelectrical signal to the control unit 160. The first reading unit 140and the second reading unit 150 face each other with a documenttransporting path 133 interposed therebetween. More particularly, thefirst reading unit 140 is located below the document D fed by theautomatic document feeder 130 to read image information from a firstside of the document, and the second reading unit 150 is located abovethe document D fed by the automatic document feeder 130 to read imageinformation from a second side of the document.

The first reading unit 140 and the second reading unit 150 arerespectively configured so as to read the first side and the second sideof the document with different capabilities. For example, a readingunit, which can support a resolution of 1200 dpi as a maximum inconsideration of a case where a high-resolution reading operation isnecessary, that is, a case where a picture is read, may be used as thefirst reading unit 140 and a reading unit which can support a resolutionof 600 dpi may be used as the second reading unit 150. A reading unitwhich can perform both a monochromic reading operation and a full-colorreading operation may be used as the first reading unit 140 and areading unit which can perform only the monochromic reading operationmay be used as the second reading unit 150. Although the first readingunit 140 and the second reading unit 150 have the same specification,the first reading unit 140 and the second reading unit 150 canrespectively read both sides of a document with different capabilitiesif a user selects different reading options with respect to the firstreading unit 140 and the second reading unit 150.

The cover 120 is rotatably coupled to the reading frame 110 so as toopen and close the upper surface of the reading frame 110. The secondreading unit 150 and the automatic document feeder 130 are mountedinside the cover 120.

The first reading unit 140 is mounted inside the reading frame 110, anda flat glass 111 and a first ADF glass 171 are mounted on the uppersurface of the reading frame 110. The user can lay the documents on theflat glass 111 one by one in order to read the documents. The firstreading unit 140 is moved along and below the flat glass 111 to read thedocument laid on the flat glass 111, and is located below the first ADFglass 171 to read the first side of the document D transported by theautomatic document feeder 130.

The automatic document feeder 130 includes a document insertion port 131through which a document to be read is inserted, a document ejectionport 132 through which the read document is ejected, the documenttransporting path 133 which is formed inside the cover 120 so as totransport the document, and rollers 135, 136 and 137 which are mountedon the document transporting path 133 so as to transport the document.

The document insertion port 131 is formed at one side of the cover 120and the document ejection port 132 is formed below the documentinsertion port 131. A document feed tray 131 a on which the documents Dto be transported by the automatic document feeder 130 are loaded and adocument insertion detection sensor 131 b to detect whether a documentis inserted and outputs the detected result to the control unit 160 areprovided in the vicinity of the document insertion port 131. A documentejection tray 132 a, on which the documents ejected after the readingoperation is completed are loaded, is provided in a vicinity of thedocument ejection port 132.

The document transporting path 133 has a C-shape. One end of thedocument transporting path 133 is connected to the document feed tray131 a via the document insertion port 131 and the other end thereof isconnected to the document ejection tray 132 a via the document ejectionport 132. The first ADF glass 171 and a second ADF glass 172 aresequentially arranged on the reading path 133 a such that the firstreading unit 140 and the second reading unit 150 can read the imageinformation recorded on the document D passing through the documenttransporting path 133. The first ADF glass 171 is mounted on the readingframe 110 at a position corresponding to the first reading unit 140 andthe second ADF glass 172 is mounted on the cover 120 at a positioncorresponding to the second reading unit 150.

The document transporting rollers include a document pickup roller 134to pick up the document D loaded on the document feed tray 131 a, firstto third transporting rollers 135, 136 and 137 to transport the documentpicked up by the document pickup roller 134 on the document transportingpath 133, an ejection roller 138 to eject the read document to thedocument ejection tray 132 a. The rollers 134, 135, 136, 137 and 138 aredriven and rotated by at least one motor (not illustrated) and transportthe document at a speed suitable to allow the first reading unit 140 andthe second reading unit 150 to read the document. The first transportingroller 135, which is provided closest to the document pickup roller 134,separates the documents picked up by the document pickup roller 134 oneby one. In order to separate the documents, a friction pad 135 a isprovided so as to be opposed to the first transporting roller 135.

The control unit 160 determines any one of the first reading unit 140and the second reading unit 150 as a reference reading unit in aboth-side reading mode in which both sides of a document are read andcontrols a driving unit 184 (see FIG. 3) such that the document can betransported at a speed suitable to allow the reference reading unit toread the document.

The control unit 160 may estimate reading times of the first readingunit 140 and the second reading unit 150 according to the reading optionselected by the user. The control unit 160 may also determine any one ofthe two reading units, which has a longer reading time, as the referencereading unit. Here, the reading time indicates a time necessary to readimage information recorded on a document having a predetermined sizewith a predetermined capability and to store the image information in amemory 183 (see FIG. 3). That is, the reading time is determined inconsideration of a time necessary for a reading unit to read imageinformation of a document and a time necessary to store the read imageinformation in the memory 183. The control unit 160 can calculate anestimated reading time on a basis of a size of the document, the readingoption selected by the user, and the specification of the reading unit.

For example, if the user sets a resolution of the first reading unit 140to 600 dpi and sets a resolution of the second reading unit 150 to 100dpi, the control unit 160 can calculate and compare the reading time ofthe first reading unit 140 and the estimated reading time of the secondreading unit 150 in consideration of specifications of the first readingunit 140 and the second reading unit 150 and the resolutions set by theuser. In this case, the first reading unit 140 having a high resolutionis determined to the reference reading unit, and the control unit 160controls a transporting speed of the document on a basis of the readingtime of the first reading unit 140. At this time, if the document istransported at a low speed according to the reading time of the firstreading unit 140, the second reading unit 150 to read the document witha low resolution reads the document more densely than is necessary.Accordingly, the control unit 160 can control the second reading unit150 such that a reading time interval of the second reading unit 150 isincreased. Here, the reading time interval indicates a time intervaluntil a reading unit reads image information from a document a secondtime after the reading unit reads the image information from thedocument once.

Although an example where the first reading unit 140 and the secondreading unit 150 read a document with different resolutions wasdescribed, the control unit 160 may estimate the reading times of thefirst reading unit 140 and the second reading unit 150 and control thetransporting speed of the document even when the user sets the readingoptions of the first reading unit 140 and the second reading unit 150,such as full-color/monochrome, to be different from each other or evenwhen the user sets the reading options such as full-color/monochrome andreading resolutions to be different from each other.

As illustrated in FIG. 3, the image reading apparatus 100 according toan embodiment of the present general inventive concept includes an inputunit 181, a display unit 182, the memory 183, and the driving unit 184.

The input unit 181 inputs information on an operation of the imagereading apparatus selected by the user to the control unit 160. The usercan select a reading mode such as a one-side reading operation or aboth-side reading operation using the input unit 181 and select which ofthe first reading unit 140 and the second reading unit 150 is used inthe one-side reading mode. In addition, the user can select and inputthe reading options (reading resolution, monochrome/full-color or thelike) of the first reading unit 140 and the second reading unit 150using the input unit 181.

The display unit 182 displays an operation state of the image readingapparatus 100 to the user. The control unit 160 can display informationon a direction of a side to be read via the display unit 182 in theone-side reading mode. The information on the direction of the side tobe read indicates information indicating whether the side to be read isdirected upward or downward when the document is laid on the documentfeed tray 131 a.

The memory 183 stores a variety of data necessary to control the imagereading apparatus. More particularly, the memory 183 stores datanecessary to estimate the reading times of the first reading unit 140and the second reading unit 150. That is, the memory 183 stores datarelated to a reading time determined according to the size of a documentto be read, data related to a reading time determined according to areading resolution, or data related to a reading time determinedaccording to a monochromic/full-color reading operation.

A buffer memory (not illustrated) may be provided in the memory 183. Thebuffer memory temporarily stores image data read by the first readingunit 140 and the second reading unit 150. The control unit 160 can readthe image data stored in the buffer memory and perform predeterminedimage processing (e.g., gamma correction or shading correction).

The driving unit 184 includes at least one motor to drive the rollers134, 135, 136, 137 and 138 provided in the automatic document feeder130. The driving unit 184 drives the motor under the control of thecontrol unit 160, rotates the rollers 134, 135, 136, 137 and 138, andtransports the document on the document transporting path 133.

Hereinafter, a method of controlling the image reading apparatusaccording to an embodiment of the present general inventive concept willbe described with reference to FIGS. 2 to 4. FIG. 4 is a flowchartillustrating a method of controlling the image reading apparatusaccording to an embodiment of the present general inventive concept.

When a power source of the image reading apparatus is turned on and adetermination is made that a document is inserted into the documentinsertion port 131 via a signal input from the document insertiondetection sensor 131 b, the control unit 160 determines whether a userinputs a reading command (operation S301). If a determination is madethat the reading command is input, the reading command input by the useris checked. At this time, the control unit 160 checks a reading modeselected by the user and a reading option selected by the user(operation S302).

Subsequently, the control unit 160 determines whether the reading modeselected by the user is a both-side reading mode (operation S303).

If a determination is made that the user selects the both-side readingmode, the control unit 160 calculates a time necessary for the firstreading unit 140 to read a first side of a document and a time necessaryfor the second reading unit 150 to read a second side of the documentaccording to the reading option selected by the user (operation S304).Then, the control unit 160 compares the reading time of the firstreading unit 140 with the reading time of the second reading unit 150calculated in Operation S304 and determines any one of the readingunits, which has a longer reading time, as a reference reading unit(operation S305).

After the reference reading unit is determined, the control unit 160determines whether the first reading unit 140 is the reference readingunit (operation S306). If a determination is made that the first readingunit 140 is the reference reading unit, the control unit 160 controlsthe driving unit 184 such that the document is transported at a speedsuitable to allow the first reading unit 140 to read the document(operation S307) and controls the reading time interval of the secondreading unit 150 such that the second reading unit 150 does not read theimage information of the document more densely than is necessary(operation S308).

Meanwhile, if a determination is made that the second reading unit 150is the reference reading unit in Operation S306, the control unit 160controls the driving unit 184 such that the document is transported at aspeed suitable to allow the second reading unit 150 to read the document(operation S309) and controls the reading time interval of the firstreading unit 140 such that the first reading unit 140 does not read theimage information of the document more densely than is necessary(operation S310).

After Operation S308 or S309 is performed, the control unit 160 controlsthe first reading unit 140 to read the first side of the document andcontrols the second reading unit 150 to read the second side of thedocument (operation S311).

Meanwhile, if a determination is made that the user does not select theboth-side reading mode in Operation S303, the control unit 160determined that an one-side reading mode is selected and determines anyone of the first reading unit 140 and the second reading unit 150, whichwill be used to read the document (operation S312). Here, the readingunit, which will be used to read one side of the document, may bedetermined by a basic setting or selection of the user.

If the reading unit which will be used to read one side of the documentis determined, the control unit 160 displays information on thedirection of a side of the document, which will be read, that is,information indicating whether a side to be read is directed upward ordownward when the document is laid on the document feed tray 131 a, tothe user (operation S313). More particularly, if the first reading unit140 is determined as the reading unit which will be used to read oneside of the document, the control unit 160 instructs the user to lay thedocument on the document feed tray 131 a in a state in which thedocument is provided to be suitable to allow the first reading unit 140to read the document, that is, in a state in which the side to be readis directed upward. In contrast, if the second reading unit 150 isdetermined as the reading unit which will be used to read one side ofthe document, the control unit 160 instructs the user to lay thedocument on the document feed tray 131 a in a state in which thedocument is provided to be suitable to allow the second reading unit 150to read the document, that is, in a state in which the side to be readis directed downward.

Subsequently, the control unit 160 controls the driving unit 184 totransport the document loaded on the document feed tray 131 a at anappropriate speed and, at the same time, controls the first reading unit140 or the second reading unit 150 to read the first side or the secondside of the document (operation S314).

If the reading process of Operation S311 or S314 is completed, thecontrol unit 160 controls the read image information to be stored as afile or to be printed via the printing apparatus 200 according to theselection of the user (operation S315).

The present general inventive concept can also be embodied ascomputer-readable codes on a computer-readable medium. Thecomputer-readable medium can include a computer-readable recordingmedium and a computer-readable transmission medium. Thecomputer-readable recording medium is any data storage device that canstore data that can be thereafter read by a computer system. Examples ofthe computer-readable recording medium include read-only memory (ROM),random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, andoptical data storage devices. The computer-readable recording medium canalso be distributed over network coupled computer systems so that thecomputer-readable code is stored and executed in a distributed fashion.The computer-readable transmission medium can transmit carrier waves orsignals (e.g., wired or wireless data transmission through theInternet). Also, functional programs, codes, and code segments toaccomplish the present general inventive concept can be easily construedby programmers skilled in the art to which the present general inventiveconcept pertains.

As described above, according to various embodiments of the presentgeneral inventive concept, preventing reading quality from deterioratingis accomplished by controlling a transporting speed of a document suchthat a first reading unit and a second reading unit sufficiently performfunctions thereof when the two reading units respectively read bothsides of the document with different capabilities.

Although various embodiments of the present general inventive concepthave been illustrated and described, it would be appreciated by thoseskilled in the art that changes may be made in these embodiments withoutdeparting from the principles and spirit of the general inventiveconcept, the scope of which is defined in the appended claims and theirequivalents.

What is claimed is:
 1. An image reading apparatus, comprising: a firstreading unit to read one side of the document; a second reading unit toread an other second side of the document; an input unit to providefirst reading options corresponding to a first reading unit and secondreading options corresponding to a second reading unit from which a usercan select; and a control unit to selectively control the first readingunit and the second reading unit based on the respective first andsecond reading options selected by the user, where the respective optionselected by the user for each of the first reading unit and the secondreading unit are different from each other.
 2. The apparatus of claim 1,wherein the first and second reading options comprise: a colorcapability, a monochrome capability and resolution capabilities.
 3. Theapparatus of claim 1, wherein the control unit selectively controls atransport speed of the document to the first reading unit and the secondreading unit based on the respective first reading options and secondreading options selected by the user.
 4. An image reading method,comprising: providing first reading options corresponding to a firstreading unit and second reading options corresponding to a secondreading unit from which a user can select; and selectively controllingthe first reading unit and the second reading unit based on therespective first and second reading options selected by the user, wherethe respective option selected by the user for each of the first readingunit and the second reading unit are different from each other.
 5. Anon-transitory computer-readable recording medium having embodiedthereon a computer program to execute a method, wherein the methodcomprises: providing first reading options corresponding to a firstreading unit and second reading options corresponding to a secondreading unit from which a user can select; and selectively controllingthe first reading unit and the second reading unit based on therespective first and second reading options selected by the user, wherethe respective option selected by the user for each of the first readingunit and the second reading unit are different from each other.